diff options
Diffstat (limited to 'drivers/iommu/arm-smmu.c')
| -rw-r--r-- | drivers/iommu/arm-smmu.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 83f50142e63e..618e133f643a 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -162,6 +162,7 @@ #define ARM_SMMU_GR0_sTLBGSTATUS 0x74 #define sTLBGSTATUS_GSACTIVE (1 << 0) #define TLB_LOOP_TIMEOUT 1000000 /* 1s! */ +#define TLB_SPIN_COUNT 10 /* Stream mapping registers */ #define ARM_SMMU_GR0_SMR(n) (0x800 + ((n) << 2)) @@ -574,18 +575,19 @@ static void __arm_smmu_free_bitmap(unsigned long *map, int idx) static void __arm_smmu_tlb_sync(struct arm_smmu_device *smmu, void __iomem *sync, void __iomem *status) { - int count = 0; + unsigned int spin_cnt, delay; writel_relaxed(0, sync); - while (readl_relaxed(status) & sTLBGSTATUS_GSACTIVE) { - cpu_relax(); - if (++count == TLB_LOOP_TIMEOUT) { - dev_err_ratelimited(smmu->dev, - "TLB sync timed out -- SMMU may be deadlocked\n"); - return; + for (delay = 1; delay < TLB_LOOP_TIMEOUT; delay *= 2) { + for (spin_cnt = TLB_SPIN_COUNT; spin_cnt > 0; spin_cnt--) { + if (!(readl_relaxed(status) & sTLBGSTATUS_GSACTIVE)) + return; + cpu_relax(); } - udelay(1); + udelay(delay); } + dev_err_ratelimited(smmu->dev, + "TLB sync timed out -- SMMU may be deadlocked\n"); } static void arm_smmu_tlb_sync_global(struct arm_smmu_device *smmu) |